beaten up wood cabinets?

We're putting a bid on a house (yay!) though it has kind of beaten up wood cabinets in the kitchen.  They have good bones and I like the style and wood, but the wood itself is a little beaten up and the shiny finish is worn off most of the cabinets.  I know nothing about wood cabinets (ours are painted).  Can I just clean them really well and put on a coat of polyurethane or would they need to be stripped and redone?  I'm looking for a quick fix for now, that would make them look nice with a minimum of work at least for the time being.

Any advice?